Chromium perchlorate, 6-hydrate

These and related incidents are detailed under f Acetonitrile, Lanthanide perchlorate, 0758 Chromium(III) perchlorate. 6 dimethyl sulfoxide Cobalt(II) perchlorate hydrates, 4051... 

Chlorophenyl)pyridazin-3-yl]hydrazine was obtained following the literature procedure. Iron(iii) perchlorate hydrate, chromium(iii) perchlorate hexa-hydrate and squaric acid were purchased from commercial sources and used without any further purification. A dipotassium squarate solution was prepared by adding the required quantity of solid potassium hydroxide to an aqueous solution of squaric acid. The metal content was determined by atomic absorp tion spectrometry. The molar conductivities were measured in 10 solutions. 

O32Cl8FeMn5N36Cii4Hi50 5H2O, Iron, hexa-kis cyano( 1,4-bis(2-pyridyImethyI)-1,4,7-triazacyclononane) manganese(II) -, octa-perchlorate, pentahydrate, 34 137 036Cl9CrCu6N3oC42Hio8-H20, Chromium, hexakis cyano(tris(2-aminoethyl)amine)-copper(II) -, nonaperchlorate, hydrate, 34 138... 

In gravimetric analysis, the solution-preparation step has its own special significance. The analyte must be separated from interfering species, or the interferents must be masked. For example, if iron(III) is to be estimated as its hydrated oxide in the presence of chromium(III), then the mixture is initially treated with perchloric acid so as to oxidize chromium(III) to chromate (chromium(VI), Cr04 ), followed by addition of ammonia to precipitate the hydrated iron oxide. Sometimes it is necessary to remove interferents, for example, when calcium is to be estimated as calcium sulfate in the presence of barium. The barium is removed as its chromate and the calcium is precipitated quantitatively as its sulfate. 

The hydrated chromium(III) cation formed in the hydrolysis solution is strongly adsorbed on the resin, but can be removed from the column with a solution containing 0.5 M perchloric acid and 2.5 M sodium perchlorate. It is identified in the effluent by its typical three-band ultraviolet and visible absorption spectrum with, maxima at 575, 406, and 256 m/i (Fig. 4), and comprises about 11 % of the hydrolysis mixture. 

CsHaaClaCOjNaOi 5 HjO, /n-Peroxo-/i-hydroxo-bis[bis(ethylenediamine)-cobalt(III)] perchlorate monohydrate, 46B, 953 CsHa aCr2NeOi uSi, H2O, A,A-/i-Hydroxo-/i-sulfatobis[bis(ethylenediam-ine)chromium(III)] dithionate hydrate, 45B, 1026 C8H3ftBr3Co2NgOi,S, DL /i-Amido-/i-sulfato-bis(bis(ethylenediamine)co-balt(III)) tribromide, 37B, 486... 

Monodisperse particles of hydrated chromium oxide Cr203 can be obtained by prolonged healing around 75 °C of diluted solutions of KCr(S04)2- I6H2O [2,77] (Figure 5.19). The specific role of sulfate is clear since, under similar conditions, chromium nitrate or perchlorate yield only soluble hydrolysis products. 

Diperchlorate Dihydrazine Chromium(III) Perchlorate Diperchlorate dihydrazine chromium(III) perchlorate, [Cr(C104)2(N2H4)2] CIO4, is prepared by the addition of alcoholic hydrazine hydrate to an aqueous solution of chromium(ni) perchlorate. The reaction is instantaneous with the formation of a crystalfine violet compoimd [32]. 

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